The present invention relates to a seat cushion.
Such seat cushions are principally used, in practice, in the back-seat area of vehicles, where space is limited and usually there is no installation space available for bolting the seat cushions to the vehicle. The seat cushion nevertheless needs to be immovably anchored and easy to install.
German Published Patent Application No. 195 24 174 describes a seat cushion that has a locking apparatus having a wire spring that coacts with a catch head. Upon assembly, the seat cushion locks automatically by the application of pressure from above onto the seat cushion, whereupon the wire spring is spread apart by the catch head and then engages in interlocking fashion behind it. A disadvantage with this apparatus is that the introduction of large forces can cause the wire spring to yield and bend. The risk then exists that it may come out of engagement with the catch head and release the seat cushion.
It is an object of the present invention to provide a seat cushion that may be easily installed and easily replaced, in which context the seat cushion may not accidentally come loose when large forces occur.
The above and other beneficial objects of the present invention may be achieved by providing a seat cushion as described herein.
An example embodiment of a seat cushion has a locking apparatus having a two-limbed wire spring that engages behind a mushroom head. The two limbs of the wire spring are joined to one another at one end and open at the other end. The wire spring may be arranged, for example, from one piece of spring wire that is appropriately shaped. At the open end, the limbs of the wire spring each have an eye which, when the locking apparatus is locked, engages behind a strut shaped onto the cushion shell. The two limbs of the wire spring are fixed at both ends and may not move away from one another. At one end the limbs are joined to one another, and at the other end they are immobilized by the eyes that are in engagement with the cushion shell. As a result, in the locked position the wire spring may always be in engagement with the mushroom head. The locking apparatus may thus remain securely locked even when large forces are introduced.
To allow easy replacement of the seat cushion, provision may be made for the locking apparatus to be arranged disengageably. It has a manual actuation element that is joined to the wire spring, e.g., retains the joined end of the wire spring. The actuation element transfers the pressure introduced by manual actuation directly to the wire spring and forces it in the opening direction.
An example embodiment provides for the spring to be arranged in approximately a U-shape, the limbs of the wire spring being shaped and/or positioned as mirror images of one another. Each limb may have at least one obliquely extending segment that coacts with an oblique guidance surface, e.g., a spreader element. When the wire spring is acted upon in the opening direction, it moves linearly along the oblique guidance surface, is spread as a result of the obliquely shaped limb segments, and comes out of engagement with the mushroom head.
An example embodiment provides for the wire spring to have a spring tension that moves the two limbs toward one another. By coaction of the spreader wedges and the oblique segments of the spring limbs, the spring tension forces the wire spring in the closing direction, so that the locking apparatus automatically locks.
A further example embodiment provides for the strut beneath which the eye engages to be arranged as a spreader wedge. The strut may have on one side a pocket and/or a groove into which the eye engages. The other side of the strut may be arranged as an oblique surface that is in contact with, and guides, an oblique segment of the limb of the wire spring.
To ensure easy actuation of the locking apparatus on the one hand and secure retention of the seat cushion on the other hand, provision may be made for each limb of the wire spring to have at least two oblique segments. A first oblique segment is positioned before the mushroom head and a second after the mushroom head, in order to immobilize the wire spring on both sides of the mushroom head. The oblique segments may be arranged such that they at least partially wrap around the wire spring and thus guide and retain it.
Provision may be made for use of the seat cushion according to the present invention in bench seats and individual seats in the back-seat area of a vehicle and/or in individual seats e.g., in buses or rail vehicles or aircraft, etc.
Further aspects and example embodiments of the present invention are described below with reference to the Figures. The features and feature combinations described above and described below are usable not only in the particular combination indicated but also in other combinations or in isolation, without departing from the scope of the present invention.
Further example embodiments of the present invention are depicted and explained in the Figures.